The formulae given here for measuring the parameters of nine kinds of gears, worms and worm wheels have been proved in practice to be applicable.

This paper discusses the mesh theory, mesh parameters and strength of ring worm and roller worm gear drives, and provides the calculation formulas for the design of this kind of drives.

In this thesis, planar double-enveloping worm gear pairs is the research object, combined with space Meshing theory, derived from the multi-parameter modification of the mesh equation.